DESCRIPTION (provided by candidate): This is a request for a Mentored Patient-Oriented Research Career Development Award (K23) to provide Dr. Christopher Kratochvil with the training and mentorship necessary to establish himself as an independent clinical researcher in early childhood psychopharmacology, an area identified by the NIMH as having the highest priority for training new investigators. John March, M.D., M.P.H., Professor of Psychiatry at Duke University Medical Center, and William J. Burke, M.D., Professor of Psychiatry at the University of Nebraska Medical Center, will serve as Co-Primary Mentors for the Award. The career development plan includes didactics, mentorship in pediatric clinical research, and a two-phase clinical trial. The didactic agenda, which is closely integrated with the research plan, provides a systematic course of study in research design, biostatistics, epidemiology, pharmacokinetics, child development, and the ethics of biomedical research. Coursework will be conducted through the Master of Science program at University of Nebraska Medical Center. Local and national experts in preschool psychopharmacology, research design, ethics in human subject research, biostatistics, developmental behavioral pediatrics, and diagnostic assessment of preschoolers will provide mentorship. The clinical research experience includes a two-stage assessment of atomoxetine, a selective noradrenergic reuptake inhibitor, in young children with ADHD. Stage I is an open-label feasibility trial assessing the study design and methodology in children ages 5-6. Stage II is a randomized, double-blind, placebo-controlled trial evaluating safety, tolerability, and efficacy in this same population, These trials will be an experiential educational opportunity, while providing pilot data for future independent research, and will set the stage for an R01 submission in preschool psychopharmacology in year 4 of the Award period. Upon completion of this Award, the candidate will have established an externally funded independent research career in early childhood psychopharmacology, with a secondary focus on ethical issues pertaining to clinical research with children.